The fifth Gordon Research Conference on the Biology of Spirochetes will be held in January 2002 in Ventura, California. The Biology of Spirochetes Conference is unique. This is the only ongoing international meeting devoted to discussions on basic research of all medically important and biologically relevant spirochetes, a unique group of Eubacteria. Many spirochetes are pathogens and cause a variety of diseases, including syphilis, Lyme disease, relapsing fever, leptospirosis, periodontal disease, digital dermatitis of cattle, and swine and human dysentery. Historically, spirochetes have been difficult to study. These bacteria often have fastidious nutritional requirements and some have yet to be successfully cultured in vitro. Methods for genetic manipulation and mutational analysis of several spirochete species do not exist. The opportunity for exchange of ideas among groups working on different spirochetes has been one of the greatest benefits of past conferences, particularly in the area of new techniques for genetic manipulation. The application of genetic advancements and the availability of genomic sequences of Borrelia burgdorferi, Treponema pallidum, T. denticola, and new sequencing projects in Leptospira spp, are proving a wealth of new information. Combined, these data are being integrated into ongoing studies on the physiology, structure, pathogenesis, and immunobiology of these bacteria. Each of the previous Biology of Spirochetes conferences have been highly successful, receiving high praise by attendees, forging new collaborations, providing a forum for presenting state-of-the-art research on these bacteria, and helping to set new research directions. As in previous conferences, we expect attendance at the 2002 conference to reach the maximum of 150 faculty, graduate students, postdoctoral fellows, and industrial scientists. A broad spectrum of scientists representing different research interests, geographic locations, and seniority will be invited to attend. Special efforts will be made to insure strong attendance of young investigators (graduate students, post-docs and junior faculty), and achieve a balance in gender and ethnicity of attendees. The oral and poster-presentations are organized to provide many opportunities for discussion, the exchange of ideas, and development of collaborations. Funding from the National Institutes of Health is requested to partially offset the travel and registration expenses of the participating graduate students, fellows, and junior faculty members.